The 1973 Commercial Union Assurance Grand Prix was a professional tennis circuit administered by the International Lawn Tennis Federation (ILTF) which served as a forerunner to the current Association of Tennis Professionals (ATP) World Tour and the Women's Tennis Association (WTA) Tour. The circuit consisted of the four Grand Slam tournaments and open tournaments recognised by the ILTF. The Commercial Union Assurance Masters, Davis Cup Final and Federation Cup are included in this calendar but did not count towards the Grand Prix.
Key
The list of winners and number of singles titles won, alphabetically by last name:
Vijay Amritraj (2) Bretton Woods, New Delhi
Arthur Ashe (2) Chicago WCT, Washington, D.C.
John Austin (1) Aptos
Ross Case (1) Manila
Jimmy Connors (10) Baltimore, Roanoke, Salt Lake City, Salisbury, Hampton, Paramus, Boston, Columbus, Quebec, Australian Open
Mark Cox (2) Denver WCT, Eastbourne
Eddie Dibbs (3) Jackson, Hamburg, Fort Worth
Colin Dibley (1) Lacosta WCT
Mike Estep (1) Merion
Brian Fairlie (1) London WCT
Jaime Fillol (1) Tanglewood
Tom Gorman (2) Vancouver WCT, Stockholm
Brian Gottfried (2) Johannesburg WCT, Las Vegas
Clark Graebner (1) Des Moines
Jiří Hřebec (1) Prague
Jan Kodeš (2) Cologne WCT, Wimbledon
Rod Laver (5) Miami WCT, Richmond WCT, Toronto WCT, Hong Kong, Sydney Indoor
Sandy Mayer (1) Birmingham
Ilie Năstase (14) Omaha, Calgary, Barcelona, Monte Carlo, Madrid, Florence, French Open, Rome, Queen's Club, Gstaad, Cincinnati, Trofeo Godó, Paris Bercy, Masters
John Newcombe (2) Jakarta, US Open
Tom Okker (6) Washington WCT, Hilversum, Montreal, Seattle, Madrid, London
Manuel Orantes (3) Valencia, Nice, Louisville
Adriano Panatta (1) Bournemouth
Hans-Jürgen Pohmann (2) Berlin, Düsseldorf
Raúl Ramírez (2) Kitzbühel, Tehran
Marty Riessen (1) Milan WCT
Ken Rosewall (4) Houston WCT, Cleveland WCT, Charlotte WCT, Osaka
Stan Smith (7) Philadelphia WCT, Atlanta WCT, St. Louis WCT, Munich WCT, Gothenburg WCT, Dallas WCT, Båstad
Fred Stolle (1) Christchurch
Roger Taylor (2) Copenhagen WCT, Newport
Erik Van Dillen (1) Nottingham
Guillermo Vilas (1) Buenos Aires
The following players won their first title in 1973:
Vijay Amritraj Bretton Woods
John Austin Aptos
Ross Case Manila
Eddie Dibbs Jackson
Mike Estep Merion
Brian Fairlie London WCT
Brian Gottfried Johannesburg WCT
Jiří Hřebec Prague
Sandy Mayer Birmingham
Adriano Panatta Bournemouth
Hans-Jürgen Pohmann Berlin
Raúl Ramírez Kitzbühel
Erik Van Dillen Nottingham
Guillermo Vilas Buenos Aires